Erythrocyte sphingolipid species as biomarkers of Alzheimer's disease

Abstract Diagnosing Alzheimer's disease (AD) in the early stages is challenging. Informative biomarkers could be of great value for population-based screening. Metabolomics studies have been used to find potential biomarkers, but commonly used tissue sources can be difficult to obtain. The objective of this study was to determine the potential utility of erythrocyte metabolite profiles in screening for AD. Unlike some commonly-used sources such as cerebrospinal fluid (CSF) and brain tissue, erythrocytes are plentiful and easily accessed. Moreover, erythrocytes are metabolically active, a feature that distinguishes this sample source from other bodily fluids like plasma and urine. In this preliminary pilot study, the erythrocyte metabolomes of 10 histopathologically confirmed AD patients and 10 patients without AD (CTRL) were compared. Whole blood was collected post-mortem and erythrocytes were analyzed using ultra-performance liquid chromatography tandem mass spectrometry (UPLC/MS-MS). Over 750 metabolites were identified in AD and control (CTRL) erythrocytes. Seven were increased in AD and 24 were decreased (P